Grass ID is very challenging and fine details are needed to separate even common turf types. That said, if this lawn turns straw-brown in winter, it's almost certainly zoysia. If it doesn't, it's probably the commonly-grown tall fescue or tall fescue blend (though other cool-season grass types are in the minority in such seed mixes). If you're interested in trying to make an ID (keeping in mind you may have several species present in a blended lawn from the seed mixes used up to this point), you can use the resources linked below to take a closer look:

• Turfgrass Identification
• Cool-season Turfgrass Identification

The growth habit of the grass might also be influenced by its growing conditions, so shady or semi-shady locations, sites with compacted soil and/or regular foot traffic, over-fertilization, too much soil moisture, and other factors could be causing the plants to grow floppier and therefore more prone to a less tidy look. If the lawn wasn't mowed regularly, that too could let the blades get longer and begin to flop, and it can alter how the grass grows since it's not responding to being "grazed" (essentially) by keeping growth points closer to the ground. For example, tall fescue should be mowed to a height of about three or four inches.

Miri